Identification and functional characterization of laminin receptor in the mud crab, Scylla paramamosain, in response to MCDV-1 challenge.

Laminin receptor (LR), which mediating cell adhesion to the extracellular matrix, plays a crucial role in cell signaling and regulatory functions. In the present study, a laminin receptor gene (SpLR) was cloned and characterized from the mud crab (Scylla paramamosain). The full length of SpLR contained an open reading frame (ORF) of 960 bp encoding 319 amino acids, a 5' untranslated region (UTR) of 66 bp and a 3' UTR of 49 bp. The predicted protein comprised two Ribosomal-S2 domains and a 40S-SA-C domain. The mRNA of SpLR was highly expressed in the gill, followed by the hepatopancreas. The expression of SpLR was up-regulated after mud crab dicistrovirus-1(MCDV-1) infection. Knocking down SpLR in vivo by RNA interference significantly down-regulated the expression of the immune genes SpJAK, SpSTAT, SpToll1, SpALF1 and SpALF5. This study shown that the expression level of SpToll1 and SpCAM in SpLR-interfered group significantly increased after MCDV-1 infection. Moreover, silencing of SpLR in vivo decreased the MCDV-1 replication and increased the survival rate of mud crabs after MCDV-1 infection. These findings collectively suggest a pivotal role for SpLR in the mud crab's response to MCDV-1 infection. By influencing the expression of critical innate immune factors and impacting viral replication dynamics, SpLR emerges as a key player in the intricate host-pathogen interaction, providing valuable insights into the molecular mechanisms underlying MCDV-1 pathogenesis in mud crabs.

Clinical effect of vein of Marshall ethanol infusion on mitral isthmus ablation.

Purpose: This study aimed to investigate the effect of Marshall ethanol infusion (VOM-Et) in the vein on mitral isthmus (MI) ablation. Methods: Patients with persistent atrial fibrillation (AF) were grouped into vein of VOM-Et combined with radiofrequency (RF) ablation (VOM-Et-RF) and RF groups. The primary outcome was MI block immediate block rate after surgery. Stratified analysis was also performed for factors affecting the outcome measures. Results: A total of 118 consecutive patients underwent AF ablation at Taizhou Hospital of Zhejiang Province from January 2018 to December 2021. Successful bidirectional perimitral block was achieved in 96% of patients in VOM-Et-RF (69 of 72) and in 76% of patients in the RF group (35 of 46) (P < 0.01). In the subgroup analysis, male sex, elder than 60 years, Left atrial diameter <55 mm, and AF duration <3 years were associated with the benefits of VOM-Et in AF Patients. Conclusion: The vein of Marshall ethanol infusion for catheter ablation can improve the MI block rate. Male sex, elder age, smaller Left atrial diameter and shorter AF duration may have significant benefits for VOM-Et.

Insights into serum metabolic biomarkers for early detection of incident diabetic kidney disease in Chinese patients with type 2 diabetes by random forest.

Diabetic kidney disease (DKD) is a leading cause of end-stage renal disease (ESRD) worldwide. Early detection is critical for the risk stratification and early intervention of progressive DKD. Serum creatinine (sCr) and urine output are used to assess kidney function, but these markers are limited by their delayed changes following kidney pathology, and lacking of both sensitivity and accuracy. Hence, it is essential to illustrate potential diagnostic indicators to enhance the precise prediction of early DKD. A total of 194 Chinese individuals include 30 healthy participants (Stage 0) and 164 incidents with type 2 diabetes (T2D) spanning from DKD's Stage 1a to 4 were recruited and their serums were subjected for untargeted metabolomic analysis. Random forest (RF), a machine learning approach, together with univariate linear regression (ULR) and multivariate linear regression (MvLR) analysis were applied to characterize the features of untargeted metabolites of DKD patients and to identify candidate DKD biomarkers. Our results indicate that 2-(α-D-mannopyranosyl)-L-tryptophan (ADT), succinyladenosine (SAdo), pseudouridine and N,N,N-trimethyl-L-alanyl-L-proline betaine (L-L-TMAP) were associated with the development of DKD, in particular, the latter three that were significantly elevated in Stage 2-4 T2D incidents. Each of the four metabolites in combination with sCr achieves better performance than sCr alone with area under the receiver operating characteristic curve (AUC) of 0.81-0.91 in predicting DKD stages. An average of 3.9 years follow-up study of another cohort including 106 Stage 2-3 patients suggested that "urinary albumin-to-creatinine ratio (UACR) + ADT + SAdo" can be utilized for better prognosis evaluation of early DKD (average AUC = 0.9502) than UACR without sexual difference.

Efficacy and feasibility of vein of Marshall ethanol infusion during persistent atrial fibrillation ablation: A systematic review and meta-analysis.

BACKGROUND: Catheter ablation (CA) is currently used to treat persistent atrial fibrillation (PeAF). However, its effectiveness is limited. This study aimed to estimate the effectiveness of the vein of Marshall absolute ethanol injection (VOM-EI) for PeAF ablation. HYPOTHESIS: Adjunctive vein of Marshall ethanol injection (VOM-EI) strategies are more effective than conventional catheter ablation (CA) and have similar safety outcomes. METHODS: We extensively searched the literature for studies evaluating the effectiveness and safety of VOM-EI + CA compared with CA alone. The primary endpoint was the rate of acute bidirectional block of the isthmus of the mitral annulus (MIBB). The secondary endpoints were atrial fibrillation (AF) or atrial tachycardia (AT) recurrence over 30 seconds after a 3-month blanking period. Weighted pooled risk ratios (RRs) and corresponding 95% confidence intervals (CIs) were calculated using a random effects model. RESULTS: Based on the selection criteria, nine studies were included in this systematic review, including patients with AF (n = 2508), persistent AF (n = 1829), perimitral flutter (n = 103), and perimitral AT (n = 165). There were 1028 patients in the VOM-EI + CA group and 1605 in the CA alone group. The VOM-EI + CA group showed a lower rate of AF/AT relapse (RR = 0.70; 95% CI = 0.53-0.91; p = .008) and a higher rate of acute MIBB (RR = 1.29; 95% CI = 1.11-1.50; p = .0007) than the CA alone group. CONCLUSION: Our meta-analysis revealed that adjunctive VOM-EI strategies are more effective than conventional CA and have similar safety outcomes.

HIF-1-mediated regulation of LDH gene unravels key insights into MCDV-1 pathogenesis in mud crabs Scylla paramamosain.

Hypoxia-inducible factors -1 (HIF-1) is a crucial transcription factor that regulates the expression of glycolytic genes. Our previous study proved that the Mud crab dicistrovirus-1 (MCDV-1) can induce aerobic glycolysis that favors viral replication in mud crab Scylla paramamosain. However, the role of HIF-1 on key glycolytic genes during the MCDV-1 infection has not been examined. In this study, the intricate interplay between HIF-1 and the key glycolysis enzyme, lactate dehydrogenase (LDH), was investigated after MCDV-1 infection. The expression of LDH was significant increased after MCDV-1 infection. Additionally, the expression of HIF-1α was upregulated following MCDV-1 infection, potentially attributed to the downregulation of prolyl hydroxylase domains 2 expression. Subsequent examination of the SpLDH promoter identified the presence of hypoxia response elements (HREs), serving as binding sites for HIF-1α. Intriguingly, experimental evidence demonstrated that SpHIF-1α actively promotes SpLDH transcription through these HREs. To further elucidate the functional significance of SpHIF-1α, targeted silencing was employed, resulting in a substantial reduction in SpLDH expression, activity, and lactate concentrations in MCDV-1-infected mud crabs. Notably, SpHIF-1α-silenced mud crabs exhibited higher survival rates and lower viral loads in hepatopancreas tissues following MCDV-1 infection. These results highlight the critical role of SpHIF-1α in MCDV-1 pathogenesis by regulating LDH gene dynamics, providing valuable insights into the molecular mechanisms underlying the virus-host interaction.

Identification and functional characterization of activating transcription factor 6 (ATF6) from the mud crab (Scylla paramamosain) in response to hydrogen peroxide and bacterial challenge.

Activating transcription factor 6 (ATF6) is critical for regulation of unfolded protein response (UPR), which is involved in the endoplasmic reticulum (ER) proteostasis maintenance and cellular redox regulation. In the present study, a ATF6 gene from the mud crab (designated as Sp-ATF6) has been cloned and identified. The open reading frame of Sp-ATF6 was 1917 bp, encoding a protein of 638 amino acids. The deduced amino acid sequences of Sp-ATF6 contained a typical basic leucine zipper (BZIP domain). Sp-ATF6 was widely expressed in all tested tissues, with the highest expression levels in the hemocytes and the lowest in the muscle. Subcellular localization showed that Sp-ATF6 was expressed in both nucleus and cytoplasm of S2 cells. The expression level of Sp-ATF6 was induced by hydrogen peroxide and V. parahaemolyticus challenge, indicating that the ATF6 pathway was activated in response to ER stress. In order to know more about the regulation mechanism of the Sp-ATF6, RNA interference experiment was investigated. Knocking down Sp-ATF6 in vivo can decrease the expression of antioxidant-related genes (CAT and SOD) and heat shock proteins (HSP90 and HSP70) after V. parahaemolyticus infection. All these results suggested that Sp-ATF6 played a crucial role in the defense against environmental stress and pathogen infection in crustaceans.

Prognostic model of kidney renal clear cell carcinoma using aging-related long noncoding RNA signatures identifies THBS1-IT1 as a potential prognostic biomarker for multiple cancers.

Aging is responsible for the main intrinsic triggers of cancers; however, the studies of aging risk factors in cancer animal models and cancer patients are rare and insufficient to be represented in cancer clinical trials. For a better understanding of the complex regulatory networks of aging and cancers, 8 candidate aging related long noncoding RNAs (CarLncs) identified from the healthy aging models, centenarians and their offsprings, were selected and their association with kidney renal clear cell carcinoma (KIRC) was explored by series of cutting edge analyses such as support vector machine (SVM) and random forest (RF) algorithms. Using data downloaded from TCGA and GTEx databases, a regulatory network of CarLncs-miRNA-mRNA was constructed and five genes within the network were screened out as aging related feature genes for developing KIRC prognostic models. After a strict filtering pipeline for modeling, a formula using the transcript per million (TPM) values of feature genes "LncAging_score = 0.008* MMP11 + 0.066* THBS1-IT1 + (-0.014)* DYNLL2 + (-0.030)* RMND5A+ 0.008* PEG10" was developed. ROC analysis and nomogram suggest our model achieves a great performance in KIRC prognosis. Among the 8 CarLncs, we found that THBS1-IT1 was significantly dysregulated in 12 cancer types. A comprehensive pan-cancer analysis demonstrated that THBS1-IT1 is a potential prognostic biomarker in not only KIRC but also multiple cancers, such as LUSC, BLCA, GBM, LGG, MESO, PAAD, STAD and THCA, it was correlated with tumor microenvironment (TME) and tumor immune cell infiltration (TICI) and its high expression was related with poor survival.

Essential role of the HSC70 in the mud crab Scylla paramamosain in response to Vibrio parahaemolyticus infection.

Heat shock proteins play an important role in host defense, and modulate immune responses against pathogen infection. In this study, a novel HSC70 from the mud crab (designated as SpHSC70) was cloned and characterized. The full length of SpHSC70 contained a 58 bp 5'untranslated region (UTR), an open reading frame (ORF) of 2,046 bp and a 3'UTR of 341 bp. The SpHSC70 protein included the conserved DnaK motif. The mRNA of SpHSC70 was highly expressed in the hemocytes, heart and hepatopancreas, and lowly expressed in the intestine. The subcellular localization results indicated that SpHSC70 was localized in both the cytoplasm and the nucleus. Moreover, SpHSC70 was significantly responsive to bacterial challenge. RNA interference experiment was designed to investigate the roles of SpHSC70 in response to bacterial challenge. V. parahaemolyticus infection induced the expression levels of SpPO, SpHSP70, SpSOD and SpCAT. Knocking down SpHSC70 in vivo can decrease the expression of these genes after V. parahaemolyticus infection. These results suggested that SpHSC70 could play a vital role in defense against V. parahaemolyticus infection via activating the immune response and antioxidant defense signaling pathways in the mud crab.

Characterization of a novel prolyl hydroxylase 2 gene from mud crab Scylla paramamosain: Insights into its role in the regulation of hypoxia-inducible factor-1α.

Prolyl hydroxylase 2 (PHD2) is the key oxygen sensor that regulates the stability of the hypoxia-inducible factor -1α (HIF-1α). In this study, a novel PHD2 gene from the mud crab Scylla paramamosain, named SpPHD2, was cloned and identified. The full-length transcript of SpPHD2 was found to be 1926 bp, consisting of a 333 bp 5' untranslated region, a 1239 bp open reading frame, and a 354 bp 3' untranslated region. The putative SpPHD2 protein contained a Prolyl 4-hydroxylase alpha subunit homologues (P4Hc) domain in the C-terminal and a Myeloid translocation protein 8, Nervy, and DEAF-1 (MYND)-type zinc finger (zf-MYND) domain in the N-terminal. The mRNA expression of SpPHD2 was found to be widely distributed across all examined tissues. Additionally, the subcellular localization results indicated that the SpPHD2 protein was mainly localized in the cytoplasm. The in vivo silencing of SpPHD2 resulted in the upregulation of SpHIF-1α and a series of downstream genes involved in the HIF-1 pathway, while SpPHD2 overexpression in vitro dose-dependently reduced SpHIF-1α transcriptional activity, indicating that SpPHD2 plays a crucial role in SpHIF-1α regulation. Interestingly, the expression of SpPHD2 increased under hypoxic conditions, which was further inhibited by SpHIF-1α interference. Moreover, four hypoxia response elements were identified in the SpPHD2 promoter, suggesting that a feedback loop exists between SpPHD2 and SpHIF-1α under hypoxia. Taken together, these results provided new insights into the regulation of SpPHD2 in response to hypoxia in S. paramamosain.

Glutaredoxin 2 in the mud crab Scylla paramamosain: Identification and functional characterization under hypoxia and pathogen challenge.

Glutaredoxin (Grx) is a glutathione-dependent oxidoreductase that plays a key role in antioxidant defense. In this study, a novel Grx2 gene (SpGrx2) was identified from the mud crab Scylla paramamosain, which consists of a 196 bp 5' untranslated region, a 357 bp open reading frame, and a 964 bp 3' untranslated region. The putative SpGrx2 protein has a typical single Grx domain with the active center sequence C-P-Y-C. The expression analysis revealed that the SpGrx2 mRNA was most abundant in the gill, followed by the stomach and hemocytes. Both mud crab dicistrovirus-1 and Vibrioparahaemolyticus infection as well as hypoxia could differentially induce the expression of SpGrx2. Furthermore, silencing SpGrx2 in vivo affected the expression of a series of antioxidant-related genes after hypoxia treatment. Additionally, SpGrx2 overexpression significantly increased the total antioxidant capacity of Drosophila Schneider 2 cells after hypoxia, resulting in a reduction of reactive oxygen species and malondialdehyde content. The subcellular localization results indicated that SpGrx2 was localized in both the cytoplasm and the nucleus of Drosophila Schneider 2 cells. These results indicate that SpGrx2 plays a crucial role as an antioxidant enzyme in the defense system of mud crabs against hypoxia and pathogen challenge.

Essential role of the Cytochrome P450 2 (CYP2) in the mud crab Scylla paramamosain antioxidant defense and immune responses.

Cytochrome P450 (CYPs) enzymes are one of the critical detoxification enzymes, playing a key role in antioxidant defense. However, the information of CYPs cDNA sequences and their functions are lacked in crustaceans. In this study, a novel full-length of CYP2 from the mud crab (designated as Sp-CYP2) was cloned and characterized. The coding sequence of Sp-CYP2 was 1479 bp in length and encoded a protein containing 492 amino acids. The amino acid sequence of Sp-CYP2 comprised a conserved heme binding site and chemical substrate binding site. Quantitative real-time PCR analysis revealed that Sp-CYP2 was ubiquitously expressed in various tissues, and it was highest in the heart followed by the hepatopancreas. Subcellular localization showed that Sp-CYP2 was prominently located in the cytoplasm and nucleus. The expression of Sp-CYP2 was induced by Vibrio parahaemolyticus infection and ammonia exposure. During ammonia exposure, ammonia exposure can induce oxidative stress and cause severely tissue damage. Knocking down Sp-CYP2 in vivo can increase malondialdehyde content and the mortality of mud crabs after ammonia exposure. All these results suggested that Sp-CYP2 played a crucial role in the defense against environmental stress and pathogen infection in crustaceans.

Insights into the mechanisms of triptolide nephrotoxicity through network pharmacology-based analysis and RNA-seq.

Introduction: Triptolide (TPL) is a promising plant-derived compound for clinical therapy of multiple human diseases; however, its application was limited considering its toxicity. Methods: To explore the underlying molecular mechanism of TPL nephrotoxicity, a network pharmacology based approach was utilized to predict candidate targets related with TPL toxicity, followed by deep RNA-seq analysis to characterize the features of three transcriptional elements include protein coding genes (PCGs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs) as well as their associations with nephrotoxicity in rats with TPL treatment. Results & Discussion: Although the deeper mechanisms of TPL nephrotoxcity remain further exploration, our results suggested that c-Jun is a potential target of TPL and Per1 related circadian rhythm signaling is involved in TPL induced renal toxicity.

Toxic effects of cadmium exposure on intestinal histology, oxidative stress, microbial community, and transcriptome change in the mud crab (Scylla paramamosain).

Cadmium is one of hazardous pollutants that has a great threat to aquatic organisms and ecosystems. The intestine plays important roles in barrier function and immunity to defend against environmental stress. However, whether cadmium exposure caused the intestine injury is not well studied. Thus, the aim of this study was to explore the potential mechanisms of cadmium toxicity in the intestine of mud crab (Scylla paramamosain) via physiological, histological, microbial community, and transcriptional analyses. Mud crabs were exposed to 0, 0.01, and 0.125 mg/L cadmium. After a 21-day of cadmium exposure, 0.125 mg/L cadmium caused intestine damaged by decreasing superoxide dismutase and catalase activities, and increasing hydrogen peroxide and malondialdehyde levels. Integrated biological index analysis confirmed that the toxicity of cadmium exhibited a concentration-dependent manner. Comparative transcriptional analyses showed that the up-regulations of several genes associated with heat shock proteins, detoxification and anti-oxidant defense, and two key signaling pathways (PI3k-Akt and apoptosis) revealed an adaptive response mechanism against cadmium exposure. Transcriptomic analysis also suggested that cadmium exposure disturbed the expression of ion transport and immune-related genes, indicating that it has negative effects on the immune functions of the mud crab. Furthermore, the intestinal microbial diversity and composition were significantly influenced by cadmium exposure. The abundance of the dominant phyla Fusobacteria and Bacteroidetes significantly changed after cadmium exposure. KEGG pathway analysis demonstrated that cadmium exposure could change energy metabolism and environmental information processing. Overall, we concluded that excessive cadmium exposure could be potentially exerted adverse effects to the mud crab health by inducing oxidative damage, decreasing immune system, disrupting metabolic function, and altering intestinal microbial composition. These results provided a novel insight into the mechanism of cadmium toxicity on crustaceans.

Overexpression of mitogen-activated protein kinase phosphatase-1 in endothelial cells reduces blood-brain barrier injury in a mouse model of ischemic stroke.

Ischemic stroke can cause blood-brain barrier (BBB) injury, which worsens brain damage induced by stroke. Abnormal expression of tight junction proteins in endothelial cells (ECs) can increase intracellular space and BBB leakage. Selective inhibition of mitogen-activated protein kinase, the negative regulatory substrate of mitogen-activated protein kinase phosphatase (MKP)-1, improves tight junction protein function in ECs, and genetic deletion of MKP-1 aggravates ischemic brain injury. However, whether the latter affects BBB integrity, and the cell type-specific mechanism underlying this process, remain unclear. In this study, we established an adult male mouse model of ischemic stroke by occluding the middle cerebral artery for 60 minutes and overexpressed MKP-1 in ECs on the injured side via lentiviral transfection before stroke. We found that overexpression of MKP-1 in ECs reduced infarct volume, reduced the level of inflammatory factors interleukin-1ß, interleukin-6, and chemokine C-C motif ligand-2, inhibited vascular injury, and promoted the recovery of sensorimotor and memory/cognitive function. Overexpression of MKP-1 in ECs also inhibited the activation of cerebral ischemia-induced extracellular signal-regulated kinase (ERK) 1/2 and the downregulation of occludin expression. Finally, to investigate the mechanism by which MKP-1 exerted these functions in ECs, we established an ischemic stroke model in vitro by depriving the primary endothelial cell of oxygen and glucose, and pharmacologically inhibited the activity of MKP-1 and ERK1/2. Our findings suggest that MKP-1 inhibition aggravates oxygen and glucose deprivation-induced cell death, cell monolayer leakage, and downregulation of occludin expression, and that inhibiting ERK1/2 can reverse these effects. In addition, co-inhibition of MKP-1 and ERK1/2 exhibited similar effects to inhibition of ERK1/2. These findings suggest that overexpression of MKP-1 in ECs can prevent ischemia-induced occludin downregulation and cell death via deactivating ERK1/2, thereby protecting the integrity of BBB, alleviating brain injury, and improving post-stroke prognosis.

Co-CRISPR: A valuable toolkit for mutation enrichment in the gene editing of Spodoptera frugiperda.

The CRISPR/Cas9 system has been successfully applied in dozens of diverse species; although the screening of successful CRISPR/Cas9 editing events remains particularly laborious, especially for those that occur at relatively low frequency. Recently, a co-CRISPR strategy was proved to enrich the desired CRISPR events. Here, the co-CRISPR strategy was developed in the Fall armyworm, Spodoptera frugiperda, with kynurenine 3-monooxygenase gene (kmo) as a marker. The kmo mosaics induced by single-guide RNAs (sgRNAs)/Cas9 displayed the darker green color phenotype in larvae, compared with wild type (brown), and mosaic-eye adults were significantly acquired from the mosaic larvae group. In the kmo knockout strain, no significant difference was observed in larval development and adult reproduction. Acetylcholinesterase 2 (ace2) and Wnt1 were selected as target genes to construct the co-CRISPR strategy using kmo marker. By co-injection of kmo and ace2 sgRNAs, the mutant efficiency of ace2 was significantly increased in the kmo mosaic (larvae or adults) groups. Similarly, more malformed pupae with Wnt1 mutations were observed in the darker green larvae group. Taken together, these results demonstrated that kmo was a suitable visible marker gene for the application and extension of co-CRISPR strategy in Fall armyworm. Using darker green color in larvae or mosaic-eye in adults from kmo knockout as a marker, the mutant efficiency of a target gene could be enriched in a Fall armyworm group consisting of marked individuals. The co-CRISPR strategy is helpful for gene function studies by the knockout technique with no or lethal phenotypes.

Intentions of Patients with Hypertension to Receive a Booster Dose of the COVID-19 Vaccine: A Cross-Sectional Survey in Taizhou, China.

COVID-19 patients with hypertension have increased hospital complications and mortality rates. Moreover, these patients also have lower antibody titers after receiving the coronavirus disease (COVID-19) vaccine. Therefore, patients with hypertension should receive a COVID-19 vaccine booster. To promote the uptake of COVID-19 vaccine booster among hypertensive patients, this study investigated patients' willingness and factors that influence patients with hypertension to receive the COVID-19 vaccine booster. From July 2021 to August, 410 patients with hypertension were surveyed. Overall, 76.8% of patients were willing to receive the COVID-19 vaccine booster, as 82.7% of patients without comorbidities and 72.7% of patients with comorbidities were willing to receive the vaccine booster. The main factors that influenced the willingness of patients with hypertension to receive a booster dose were the preventive effect of the vaccine (χ2 = 52.827, p < 0.05), vaccine safety (χ2 = 42.423, p < 0.05), vaccine knowledge (χ2 = 7.831, p < 0.05), presence of comorbidities (χ2 = 4.862, p < 0.05), disease control (χ2 = 5.039, p < 0.05), and antihypertensive treatments (χ2 = 12.565, p < 0.05). This study's findings highlight the need to promote knowledge about booster vaccination among patients and health management. These measures would improve patients' willingness and knowledge about the vaccine and their health status, which are the main factors that influence patients' intention to receive booster vaccines.

Identification and functional characterization of glutaredoxin 5 from the mud crab (Scylla paramamosain) in response to cadmium and bacterial challenge.

Glutaredoxin (Grx) is a class molecule oxidoreductase, which plays a key role in maintaining redox homeostasis and regulating cell survival pathways. However, the expression pattern and function of Grx remain unknown in the mud crab (Scylla paramamosain). In the present study, a novel full-length of Grx 5 from the mud crab (designated as Sp-Grx 5) was cloned and characterized. The open reading frame of Sp-Grx 5 was 441 bp, which encoded a putative protein of 146 amino acids. The amino acid sequence of Sp-Grx 5 contained a typical C-G-F-S redox active motif and several GSH binding sites. Sp-Grx 5 widely existed in all tested tissues with a high-level expression in hepatopancreas. Subcellular localization showed that Sp-Grx 5 was located in the cytoplasm and nucleus. The expression of Sp-Grx 5 was significantly up-regulated after Vibrio parahaemolyticus infection and cadmium exposure, suggesting that Sp-Grx 5 was involved in innate immunity and detoxification. Furthermore, overexpression of Sp-Grx 5 could improve cells viability after H2O2 exposure. All these results indicated that Sp-Grx 5 played important roles in the redox homeostasis and innate immune response in crustaceans.

Specific Gain and Loss of Co-Expression Modules in Long-Lived Individuals Indicate a Role of circRNAs in Human Longevity.

Deep RNA sequencing of 164 blood samples collected from long-lived families was performed to investigate the expression patterns of circular RNAs (circRNAs). Unlike that observed in previous studies, circRNA expression in long-lived elderly individuals (98.3 ± 3.4 year) did not exhibit an age-accumulating pattern. Based on weighted circRNA co-expression network analysis, we found that longevous elders specifically gained eight but lost seven conserved circRNA-circRNA co-expression modules (c-CCMs) compared with normal elder controls (spouses of offspring of long-lived individuals, age = 59.3 ± 5.8 year). Further analysis showed that these modules were associated with healthy aging-related pathways. These results together suggest an important role of circRNAs in regulating human lifespan extension.

Characterization of phosphofructokinase (PFK) from mud crab Scylla paramamosain and its role in mud crab dicistrovirus-1 proliferation.

Phosphofructokinase (PFK), the key enzyme of glycolysis, can catalyze the irreversible transphosphorylation of fructose-6-phosphate forming fructose-1, 6-biphosphate. In the present study, a PFK gene from the mud crab Scylla paramamosain, named SpPFK, was cloned and characterized. The full length of SpPFK contained a 5'untranslated region (UTR) of 249 bp, an open reading frame of 2,859 bp, and a 3'UTR of 1,248 bp. The mRNA of SpPFK was highly expressed in the gill, followed by the hemocytes and muscle. The expression of SpPFK was significantly up-regulated after mud crab dicistrovirus-1 (MCDV-1) infection. Knocking down SpPFK in vivo by RNA interference significantly reduced the expression of lactate dehydrogenase after MCDV-1 infection. Furthermore, silencing of SpPFK in vivo increased the survival rate of mud crabs and decreased the MCDV-1 copies in the gill and hepatopancreas after MCDV-1 infection. All these results suggested that SpPFK could play an important role in the process of MCDV-1 proliferation in mud crab.

Hypoxia Affects the Antioxidant Activity of Glutaredoxin 3 in Scylla paramamosain through Hypoxia Response Elements.

Hypoxia is a major environmental stressor that can damage the oxidation metabolism of crustaceans. Glutaredoxin (Grx) is a key member of the thioredoxin superfamily and plays an important role in the host's defense against oxidative stress. At present, the role of Grx in response to hypoxia in crustaceans remains unclear. In this study, the full-length cDNA of Grx3 (SpGrx3) was obtained from the mud crab Scylla paramamosain, which contains a 129-bp 5' untranslated region, a 981-bp open reading frame, and a 1,183-bp 3' untranslated region. The putative SpGrx3 protein contains an N-terminal thioredoxin domain and two C-terminal Grx domains. SpGrx3 was expressed in all tissues examined, with the highest expression in the anterior gills. After hypoxia, SpGrx3 expression was significantly up-regulated in the anterior gills of mud crabs. The expression of Grx2 and glutathione S-transferases was decreased, while the expression of glutathione peroxidases was increased following hypoxia when SpGrx3 was silenced in vivo. In addition, the total antioxidant capacity of SpGrx3-interfered mud crabs was significantly decreased, and the malondialdehyde content was significantly increased during hypoxia. The subcellular localization data indicated that SpGrx3 was predominantly localized in the nucleus when expressed in Drosophila Schneider 2 (S2) cells. Moreover, overexpression of SpGrx3 reduced the content of reactive oxygen species in S2 cells during hypoxia. To further investigate the transactivation mechanism of SpGrx3 during hypoxia, the promoter region of the SpGrx3 was obtained by Genome Walking and three hypoxia response elements (HREs) were predicted. Dual-luciferase reporter assay results demonstrated that SpGrx3 was likely involved in the hypoxia-inducible factor-1 (HIF-1) pathway during hypoxia, which could be mediated through HREs. The results indicated that SpGrx3 is involved in regulating the antioxidant system of mud crabs and plays a critical role in the response to hypoxia.